EPS bearer ids go from 5 to 12 for each UE. As each new "bearer" gets created, MME selects a EPS bearer ID (EBID) for the UE. Lets say UE first creates a single bearer for connection to Internet, then it creates a single bearer (used for IMS signaling) for IMS/VoLTE and at some later point UE setsup a voice call and creates a voice bearer (as part of the IMS PDN Connection). So the Internet bearer, MME will give value 5 (this can be any value [5,12], IMS signaling bearer is given value 6 (again any value in the range [5,12] and not assigned to internet bearer) and value 7 to voice bearer. EBID values given to UE1 are independentent of EBID values given to UE2.

Each PRB has 12 subcarriers. So, in the *frequency domain* (y-axis), there are 12*6=72 subcarriers, and hence 72 resource elements. there are 84 resrouce elements, as there are 7 symbols (x-axis), so 12*7 = 84.

@@IrfanAli-nz7mb Thank you so much !!

Slides are at: github.com/irfanalii/youtube_slides

There is one UDP socket (per PGW-SGW) open and multiple TEIDs are send on that socket.Implementations may have multiple UDP sockets open for sending, with a different port number. But on each socket multiple TEIDs can be sent. The destination port number for GTP-U has to be 2152.

A resource block can be one of three: (i) SIB (SI-RNTI), (ii) Paging (P-RNTI), or (iii) UE-specific (C-RNTI). For (iii), the MAC can multiplex RRC message and data bearer, (and MAC control elements) destined to that specific UE. This is my understanding. So the figure is a simplification when it comes to UE-specific message. Good point.

@@IrfanAli-nz7mb Thank you for clarification.

Glad it was helpful. Thank you

Definitely!

I just uploaded the slides to github. github.com/irfanalii/youtube_slides

Sorry I do not have information about implementation of these algorithms either on the mobile or network end.